Flow rate control for a combine harvester unloading system

Abstract

In a grain unloading system for a combine harvester a grain bin includes a frame, the frame has a floor with a trough disposed therein. An unloading auger is disposed at least partially within the trough. An auger cover at least partially covers the auger. The auger cover has a hat for a top portion of the auger cover and a pair of gates movable between the hat and locations on the floor that are proximal to the trough. A gate adjustment structure is coupled to the pair of gates to move the pair of gates relative to the auger. A control system is coupled to the gate adjustment structure and controls the gate adjustment structure. The gates are each provided with a plurality of external projections.

The invention claimed is: 
     
       1. A grain unloading system for a combine harvester comprising:
 a grain bin comprising a frame, the frame comprising a floor with a trough disposed therein; 
 an unloading auger disposed at least partially within the trough; 
 an auger cover that at least partially covers the auger, the auger cover comprising a hat for a top portion of the auger cover and a pair of gates movable between the hat and locations on the floor that are proximal to the trough; 
 a gate adjustment structure coupled to the pair of gates to move the pair of gates relative to the auger; and 
 a control system coupled to the gate adjustment structure and configured to control the gate adjustment structure; 
 
       wherein the gates are each provided with a plurality of external projections comprising outwardly-projecting fingers that extend in a direction away from the auger to agitate and dislodge blocked crop. 
     
     
       2. The grain unloading system according to  claim 1 , wherein the control system comprises a user interface, wherein responsive to receiving a predetermined operator input at the user interface, corresponding to deactivation of a grain unloading function, the control system is configured to cause the gate adjustment structure to move the pair of gates to a closed position. 
     
     
       3. The grain unloading system according to  claim 1 , wherein the control system further comprises a sensor to detect the position of the pair of gates. 
     
     
       4. The grain unloading system according to  claim 1 , wherein the control system comprises a user interface, wherein responsive to receiving a predetermined operator input at the user interface corresponding to selection of a crop type among a plurality of selectable crop types, the control system is configured to cause the gate adjustment structure to move the pair of gates to a predetermined position. 
     
     
       5. The grain unloading system according to  claim 1 , wherein the control system is configured to receive a signal corresponding to grain unloading activation, wherein responsive to the signal, the control system is configured to cause the gate adjustment structure to variably adjust the movement of the pair of gates. 
     
     
       6. The grain unloading system according to  claim 5 , wherein the control system is configured to cause the gate adjustment structure to repeatedly raise and lower the pair of gates during unloading. 
     
     
       7. The grain unloading system according to  claim 6 , wherein the control system is configured to cause the gate adjustment structure to repeatedly raise and lower the pair of gates during unloading within a movement range of no more than 3 inches or 75 mm. 
     
     
       8. The grain unloading system according to  claim 5 , wherein the control system is configured to cause the gate adjustment structure to repeatedly raise and lower the pair of gates during unloading in response to receiving a signal corresponding to a specified crop type among a plurality of selectable crop types. 
     
     
       9. The grain unloading system according to  claim 8 , wherein the specified crop type is grass seed.